The name of the fandom will be 'second souls' and it's basically about YOUR persona (persona is kinda like an animated/drawn version of yourself) and the whole idea is:
You have this thing called 'a second soul' which is a second soul BUT this second soul is actually a spirit version of your favorite character,who gives you their powers when you fight in combat,they also turn into a full-on real state of your second soul if you: Ever need comfort,when you're being defeated at the last moment of combat or any basic help.
If you ever fall in-love with your second soul once you admit your love you will be transported to their world (where they